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A Comparison of Radio and X-Ray Morphologies of Four Clusters of Galaxies Containing Radio Halos

F. Govoni·T. A. Ensslin·L. Feretti·G. Giovannini
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Abstract

Clusters of galaxies may contain cluster-wide, centrally located, diffuse radio sources, called halos. They have been found to show morphologies similar to those of the X-ray emission. To quantify this qualitative statement we performed a point-to-point comparison of the radio and the X-ray emission for four clusters of galaxies containing radio halos: Coma, Abell 2255, Abell 2319, Abell 2744. Our study leads to a linear relation between the radio and the X-ray surface brightness in two clusters, namely Abell 2255 and Abell 2744. In Coma and A2319 the radio and the X-ray brightnesses seem to be related with a sub-linear power law. Implications of these findings within simple radio halo formation models are briefly discussed.

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F. Govoni, T. A. Ensslin, L. Feretti, G. Giovannini. 2001-01-23. A Comparison of Radio and X-Ray Morphologies of Four Clusters of Galaxies Containing Radio Halos. https://doi.org/10.1051/0004-6361%3A20010115

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